As environmental concerns come to the forefront in society, federal regulations require each generation of automobile to be more environmentally friendly than the previous. In striving to adhere to these regulations, automobile manufacturers are turning to alternative fuel vehicles that use cleaner fuels. Particularly, in recent years, auto manufacturers have looked to hydrogen-powered vehicles as an alternative to traditional gasoline powered vehicles. However, as with any new technology, hydrogen-powered vehicles have numerous challenges before they are commercially feasible. A chief concern is the efficiency of the fuel cells.
For example, a century of gasoline-powered vehicles has resulted in the public expecting cars and light trucks that travel at least 300 miles between fuel stops. Meeting that baseline target with hydrogen-powered vehicles has been difficult because hydrogen lacks the storage energy density efficiency of gasoline, given similar volumes. One kilogram of hydrogen contains the energy equivalent of a gallon of regular unleaded gasoline—a fact that is forcing automakers to search for new solutions for carrying hydrogen aboard vehicles. Therefore, to allow vehicles to travel sufficient distances to meet customer expectations, auto manufacturers are seeking to compress larger amounts of hydrogen in smaller tanks. Without sufficiently high pressures of hydrogen, hydrogen-powered vehicles are unable to obtain efficiencies to make hydrogen-powered vehicles a marketplace reality. While one might attempt to realize these efficiencies with existing tanks, such an attempt would be unsafe because the high pressure may cause these tanks to explode. Thus, because of the significant challenges involved, even the slightest increase in efficiency is a valuable contribution.
Recent advances in hydrogen-storage tanks have yielded elaborate tanks with an outer shell that includes several layers. While these storage tanks allow higher pressures than traditional steel tanks, these tanks are expensive. In addition, these tanks must be constrained to a cylindrical shape, and are likely unable to be molded into the tight, non-cylindrical confines of a vehicle's structure.
Therefore, a need exists for a hydrogen tank that can safely store high-pressure hydrogen and that may be compatible with present and future hydrogen-storage tanks. Such a hydrogen tank becomes an enabling technology for any regenerative power systems based on fuel cells. Such a tank is also useful in storing oxidizers.